Created attachment 114380 [details]
output of "strace valgrind ls"

On launching valgrind with any binary, it immediately returns an error. At first I tried with my own simple C/C++ programs and then I tried the system binaries such as ls too. I have even tried valgrind valgrind and result is just the same. The attachment contains strace output.

==1476== Memcheck, a memory error detector
==1476== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al.
==1476== Using Valgrind-3.13.0 and LibVEX; rerun with -h for copyright info
==1476== Command: ls
==1476== 

valgrind: the 'impossible' happened:
   Unsupported arch_prctl option

host stacktrace:
==1476==    at 0x580441BA: show_sched_status_wrk (m_libcassert.c:355)
==1476==    by 0x580442D4: report_and_quit (m_libcassert.c:426)
==1476==    by 0x58044517: panic (m_libcassert.c:502)
==1476==    by 0x58044517: vgPlain_core_panic_at (m_libcassert.c:507)
==1476==    by 0x5804454A: vgPlain_core_panic (m_libcassert.c:512)
==1476==    by 0x580DAE22: vgSysWrap_amd64_linux_sys_arch_prctl_before (syswrap-amd64-linux.c:286)
==1476==    by 0x580A0C23: vgPlain_client_syscall (syswrap-main.c:1857)
==1476==    by 0x5809D48A: handle_syscall (scheduler.c:1126)
==1476==    by 0x5809EBB6: vgPlain_scheduler (scheduler.c:1443)
==1476==    by 0x580AED50: thread_wrapper (syswrap-linux.c:103)
==1476==    by 0x580AED50: run_a_thread_NORETURN (syswrap-linux.c:156)

sched status:
  running_tid=1

Thread 1: status = VgTs_Runnable (lwpid 1476)
==1476==    at 0x401A1C5: ??? (in /usr/lib/ld-2.28.so)
==1476==    by 0xBFEBFBFE: ???


Note: see also the FAQ in the source distribution.
It contains workarounds to several common problems.
In particular, if Valgrind aborted or crashed after
identifying problems in your program, there's a good chance
that fixing those problems will prevent Valgrind aborting or
crashing, especially if it happened in m_mallocfree.c.

If that doesn't help, please report this bug to: www.valgrind.org

In the bug report, send all the above text, the valgrind
version, and what OS and version you are using.  Thanks.


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system details:
 - kernel: Linux arch 4.17.12-arch1-1-ARCH #1 SMP PREEMPT Fri Aug 3 07:16:41 UTC 2018 x86_64 GNU/Linux
 - distribution: Arch Linux
 - valgrind installed from official repositories (valgrind 3.13.0-7)
 - glibc 2.28-1